Starship Children’s Health Clinical Guideline Note: The electronic version of this guideline is the version currently in use. Any printed version can not be assumed to be current. Please remember to read our disclaimer.
ANTICOAGULATION
Introduction Low dose (unfractionated) heparin infusion Therapeutic (unfractionated) heparin infusion Low molecular weight heparin (LMWH) Warfarin - Warfarin Discharge Checklist
Adverse Events Forms - ADHB Heparin Chart (CR5620) - ADHB Paediatric Oral Anticoagulation Chart (CR8849) References
Introduction
These guidelines apply to infants and children in Starship Children’s Hospital. Refer to ADHB Newborn Services Guideline (NW Newborn Drug Protocol - Heparin Pharmacology) for infants within the newborn service. The following are guidelines only and may need to be adapted in individual circumstances. If you are in any doubt about a child’s anticoagulation management ask a senior medical doctor or paediatric haematologist. All anticoagulation needs to be prescribed. Heparin infusions must be prescribed on the ADHB Heparin chart (CR5620) and cross referenced on the medication record. Warfarin must be prescribed on the Paediatric Oral Anticoagulation chart (CR8849) and also cross referenced on the medication record. Prior to placement and removal of an Epidural Catheter, Heparin needs to be stopped or omitted as in the Pain Management – Epidurals & Anticoagulation – RBP
Low dose standard/unfractionated heparin infusion (prophylaxis) Indications for low dose heparin infusion Low dose heparin infusions are used for the maintenance of central venous lines and arterial lines to prevent thrombosis. PICU/ PHDU/ 23B HDU Cardiac children with single ventricle anatomy and central venous catheter (CVC) Infants < 5kg in PICU or the cardiac service with central venous catheter (CVC) Cardiac children with modified BT shunt, bi-directional cavopulmonary shunt and extracardiac fontan. Refer to PCCS guidelines: N:\Groups\INTRANET\Paediatric and Congenital Cardiac Service\PCCS Guidelines\Anticoagulation for Cavopulmonary aortopulmonary shunts Jan
2013 .doc) Post Liver Transplantation. Refer to the specific Paediatric liver transplant protocol for heparin dose and monitoring: Liver Transplant Recipient Post-Op Routine Care (Paed).pdf. Note: Infusion rates are not the same as the standard low dose protocol. Do not follow the low dose heparin protocol for liver transplant patients. Author: Editor:
Dr Nyree Cole, Roisin Daly Dr Raewyn Gavin
Service: Pharmacy, Paediatric haematology Date Reviewed: August 2012
Anticoagulation
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Starship Children’s Health Clinical Guideline Note: The electronic version of this guideline is the version currently in use. Any printed version can not be assumed to be current. Please remember to read our disclaimer.
ANTICOAGULATION Infusion preparation for low dose heparin Prepare the following low dose heparin solution for all of the above indications. Then refer to the appropriate management protocol.
(500 x weight (kg)) unfractionated heparin diluted to 50mls with 5% glucose or 0.9% sodium chloride 1ml/hr = 10 units/kg/hr Maximum 25,000 units in 50mls
Heparin infusions must be prescribed on the ADHB Heparin chart (CR5620) and cross referenced on the medication record. The only exception to this is PICU where this is charted on the 24 hour PICU flowchart.
Dose & administration of low dose heparin infusion Obtain baseline FBC, APTT and PT prior to commencing infusion. Recommended starting dose: Age 10units/kg/hr APTT 55 APTT >40
Maximum dose 500units/hour (even if patient’s weight greater than 50kg). Administer intravenously via CVC. Note: No loading dose is given In children who have had cardiac surgery, start infusion 4 hours after surgery if there is no significant bleeding. Cardiology patients weighing less than 5kg receiving aspirin should continue their low dose heparin while they have a CVC. Do not stop heparin infusion for sternal closure. For further information on preparation and administration, please refer to guardrails paediatric guidelines on ADHB Reference Viewer.
Author: Editor:
Dr Nyree Cole, Roisin Daly Dr Raewyn Gavin
Service: Pharmacy, Paediatric haematology Date Reviewed: August 2012
Anticoagulation
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Starship Children’s Health Clinical Guideline Note: The electronic version of this guideline is the version currently in use. Any printed version can not be assumed to be current. Please remember to read our disclaimer.
ANTICOAGULATION Monitoring and adjusting infusion of low dose heparin infusion
There is no ‘goal’ APTT for prophylactic (low dose) heparin infusions but APTT monitoring ensures that the patient is not therapeutically heparinised.
Check APTT 4 hours after start of infusion and adjust as in the tables below
Capillary APTT for ward patients should ideally be monitored around 8:30am, 1:30pm, 6:30pm or midnight.
Patients may need more frequent APTT monitoring if they are at increased risk of bleeding, check with consultant and/or cardiac surgeon.
Twice weekly FBC must be obtained to monitor for heparin induced thrombocytopenia.
PICU/ PHDU Patients less than 1 month of age APTT (Sec) Heparin Infusion (rate) < 45 10 unit/kg/hr 45-55 5 units/kg/hr >55 Stop infusion
Repeat APTT 12 hours 4 hours 4 hours
Patients greater than 1 month of age APTT (Sec) Heparin Infusion (rate) < 40 10 unit/kg/hr 40-50 5 units/kg/hr >50 Stop infusion
Repeat APTT 12 hours 4 hours 4 hours
23B HDU APTT (Sec) < 80
Heparin Infusion (rate) 10 unit/kg/hr
>80 or bleeding
Stop infusion and restart: -In children less than 1 month old if APTT < 55 -In children greater than 1 month old if APTT < 40
Repeat APTT Daily for 2 days then every 2 to 3 days 4 hours
Author: Editor:
Dr Nyree Cole, Roisin Daly Dr Raewyn Gavin
Service: Pharmacy, Paediatric haematology Date Reviewed: August 2012
Anticoagulation
Page:
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Starship Children’s Health Clinical Guideline Note: The electronic version of this guideline is the version currently in use. Any printed version can not be assumed to be current. Please remember to read our disclaimer.
ANTICOAGULATION Therapeutic standard/unfractionated heparin infusion (Treatment) Indications for therapeutic heparin infusion
Treatment of venous thromboembolism such as deep vein thrombosis, pulmonary embolism and sinus venous thromboses. Post operative management of mechanical heart valves or Fontan surgery Treatment of ischaemic stroke.
Note: If a cardiac patient is less than 21 days post-op please check with the cardiac surgeon before fully heparinising (consider ECHO if concerns of a pericardial effusion).
Infusion preparation for therapeutic heparin For children less than 30kg
(500 x weight (kg)) in units unfractionated heparin diluted to 50mls with 5% glucose or 0.9% sodium chloride 1ml/hr = 10 units/kg/hr
For children more than 30kg
(200 x weight (kg)) in units heparin, diluted to 50mls with 5% glucose or 0.9% sodium chloride 1ml/hr = 4 units/kg/hr
Heparin infusions must be prescribed on the ADHB Heparin chart (CR5620) and cross referenced on the medication record. The only exception to this is PICU where this is charted on the 24 hour PICU flowchart. Therapeutic heparin infusion prescriptions should include both units/kg/hr as well as the corresponding ml/hr rate.
Author: Editor:
Dr Nyree Cole, Roisin Daly Dr Raewyn Gavin
Service: Pharmacy, Paediatric haematology Date Reviewed: August 2012
Anticoagulation
Page:
4 of 12
Starship Children’s Health Clinical Guideline Note: The electronic version of this guideline is the version currently in use. Any printed version can not be assumed to be current. Please remember to read our disclaimer.
ANTICOAGULATION Dose & administration of therapeutic heparin infusion Obtain baseline FBC, APTT PT and renal function prior to commencing infusion. Recommended loading dose and initial maintenance dose Age Dosing
1 year 30kg
Loading dose
Initial maintenance dose
75units/kg (maximum 7200units) over 10 minutes* (See exceptions below)
28 units/kg/hr 20 units/kg/hr 18 units/kg/hr
*Give IV bolus 75 units/kg (max 7200units) over 10 minutes except: In the presence of a pre-existing coagulopathy-please discuss with senior medical doctor. If patient is already anticoagulated and /or converting from warfarin. If patient has had recent surgery - please discuss with surgeon. If more rapid heparinisation is required then 100-200 units/kg may be given after discussion with senior medical doctor. Further guidance Administer intravenously via dedicated peripheral or central line. The infusion must not be stopped or interrupted for other medication as heparin has a short half life. The duration of heparin therapy is dependent upon the primary problem, discuss with senior medical doctor or paediatric haematologist. Usual maximum dose is 2100units/hr. In patients at increased risk of bleeding maximum dose is 1000units/hr. Please discuss with senior medical doctor or paediatric haematologist. For further information on preparation and administration, please refer to guardrails paediatric guidelines on ADHB Reference Viewer.
Monitoring and adjusting therapeutic infusions of heparin
Goal APTT is usually 60 -80 for infants less than 1 month and 50-80 for children. APTT is checked 4 - 6 hours after infusion has been started and adjusted as follows: APTT (sec) < 40 40 – 49 50 – 80 81 – 90 91 – 115 > 115
Bolus (u/kg) 50 No No No No No
Stop Infusion (min) No No No No 30 60
% Rate Change Increase by 10% Increase by 10% No change Decrease by 10% Decrease by 10% Decrease by 15%
Repeat APTT 4 – 6 hours 4 – 6 hours Once/twice daily 4 – 6 hours 4 – 6 hours 4 – 6 hours
Author: Editor:
Dr Nyree Cole, Roisin Daly Dr Raewyn Gavin
Service: Pharmacy, Paediatric haematology Date Reviewed: August 2012
Anticoagulation
Page:
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Starship Children’s Health Clinical Guideline Note: The electronic version of this guideline is the version currently in use. Any printed version can not be assumed to be current. Please remember to read our disclaimer.
ANTICOAGULATION
Ensure the heparin infusion is adjusted as soon as possible after the APTT result is available and the next APTT is done 4 - 6 hours following the infusion adjustment. Nursing staff should contact relevant medical staff as soon as APTT result is available for review to ensure prompt dose changes are made as appropriate. Once stable the APTT must be checked twice daily for PICU/ PHDU patients and daily for ward based patients. Capillary APTT for ward patients should ideally be monitored around 8:30am, 1:30pm, 6:30pm and midnight. Samples must not be taken from the same line as the heparin infusion or from veins proximal to infusion. Twice weekly FBC (including platelet count) are required. If there is an abrupt decrease in platelet count (approximately 50%) consider heparin induced thrombocytopaenia (HIT) and discuss with paediatric haematologist.
Note: Avoid IM injections and arterial puncture during anticoagulant therapy. When such procedures are clinically necessary, ensure adequate external pressure is applied post-procedure. Avoid aspirin and anti-platelet medications during heparin therapy unless directed otherwise.
Low molecular weight heparin (LMWH) In infants and children, the LMWH of choice at Starship is Enoxaparin (Clexane®).
Indications for LMWH
Treatment and prophylaxis of venous thromboembolism such as deep vein thrombosis, pulmonary embolism and sinus venous thromboses.
The decision to use LMWHs instead of standard/unfractionated heparin or warfarin depends on the clinical scenario and individual patient factors such as bleeding risk or ease of venous access.
Dose & administration of LMWH Obtain baseline FBC, APTT, PT and renal function prior to commencing. Age
Prophylactic dose #
Treatment dose
2
Until anti-Xa level
